package com.example6;

import java.util.HashMap;
import java.util.Map;

public class PerformanceTest {
    public static void main(String[] args) {




    }

    public static void t1() {
        Map<Integer, String> map = new HashMap<>();
        map.put(1,"BO");
        map.put(2,"SUN");
        map.put(1,"ad");
        //键值一样，自动替换
        System.out.println(map.size());
        System.out.println(map.get(1));
    }

    public static void t2() {
        Map<Student, String> map = new HashMap<>();
        Student s1 = new Student("SUN");
        map.put(s1,"BO");
        map.get(s1);
    }
}
